Apparatus and process for utilizing coal



Dec. 25, 1928.

H. S. REED ET AL APPARATUS AND PROCESS FOR UTILIZING COAL 0N @Winer-OU E.'Arv: E n

Dec. 25, 1928.

H. S. REED ET AL APPARATUS AND PROCESS FOR UTILIZ'ING COAL Filed Oct.16, 1925 2 Sheets-Sheet 2 Patented Dec. 25, 1928.

UNITED STATES HARRY S'. REED, 0F EAST LANSING, AND

RALPH D. LAMIE, 0F LANSING, MICHIGAN.

APPARATUS AND PROCESS FOR UTILIZIING COAL.

Application tiled- October 16, 1925. Serial No. 62,856.

The object of this invention is the more elicient utilization of coal byproviding an apparatus and process for (1) recovering the valuablevolatile constituents of coal in the form of gas, light oil, and tar;(2) producing a coke or semi-coke in powdered form ready for use aspowdered fuel; and (3) delivering this powdered coke or semi-coke atpracticall incandescence continuously as produced to tlie fireboxl undera boiler or other furnace or to a press at the desired temperature forbriquetting. 4

A further object is to provide an equipment of low initial cost andmaintenance., of simple construction andv of large daily capacity.

Objects pertaining to details of construction and operation will appearfrom the detailed description to follow. The invention is defined andpointed out in the claims.

A structure which is a preferred embodiment of our invention isillustrated more or less diagrammatically in the accompanying drawing,forming a part of this application, in which Fig. 1 is a.generalassembly View of the apparatus, the olf-take being on reducedscale, part being a vertical longitudinal section through the apparatustaken on line 1 1 of Fig. 2, the retort being in full lines with part ofits shell broken away, and the furnace and burner for the powdered fuelbeing indicated diagrammatically.

Fig. 2 is a vertical cross section taken on line 2 2 of Figs. 1 and 10,showing details of the furnace.

Fig. 3 is an enlarged longitudinal sectional view of the retort taken onirregular line 1 1 of Fig. 2, and on line 3 3 of Figs. 4, 5, 6 and 7,the feed screws appearing in full lines.

Fig. 4 is a cross section of the retort takenk on line 4 4 of Figs. 1and 3. showing the discharge clippers and structure.

Fig. 5 is a cross section taken on line 5 5 of Figs. 1 and 3, showingthe scalloped retaining plate at the discharge end of the retort and theadjustable support-ing rollers for the revolving retort.

Fig. 6 is a cross section taken on line 6 6 of Figs. 1 and 3, showingthe partition retaining and grading plate Within the body of the retort.

Fig. 7 is a cross sectional View 7 7 of Figs. 1 and 3, screws.

Fig, 8 is a perspective view of the angular tumbllng, grinding, scrapingelements, of tetrahedral and different angular forms.

A Fig. 9 is a perspective view of the ball tumbling milling elements.

Fig. 10 is a detail plan view looking down on the top of the stack, airforcing means being omitted.

Fig. 11 is a detail vertical sectional view taken on line 11 11 of Figs.2 and 10, showing details of the flue structure and hot air supply tothe furnace burners, air pressure omitted.

Fig. 12 is a detail sectional View on line 12/ 12 of Figs. l and 3,showing details of the ilushinghpipe for steam or gas and theconnections to the device.

The parts of the drawings will be referred to by their numbers whichidentify like parts in al1 the views.

taken on line showing the feed 1 is the brick work of the furnace,which` is provided with the usual fire brick lining. 2 is the chimneystructure. 3 is a burner for the furnace. 4 is the combustion chamber orfire box. 5 is the heating chamber for heating the retort. 6 is thedirect flue from this chamber. 7 is the auxiliary indirect Hue fordirecting heat to the preheater. 8 is the cylindrical retort. 9 is thepreheater in the form of a feed conduit trough, with conveyor screw 91.10 is the bunker or hopper for supplying and feeding the coal. 11 is thetelescopic feed connection to the feed means 12. 13 is the discharge forthe residue from the retort 8. 14 is the adjustable roller support. 15is the driving gear for the retort. 16 is a steam supply. 17 is thevapor and gas outlet for the distilled material from the retort.

The furnace 1 may be heated in any suitable way, but gas for the furnaceis especially available, it being produced asa product of distillation.This is supplied to the burner through pipe 185 from the storage tank orgas holder 184. The gas burners deliver into the combustion chamber andentrain hot ai]` `from the down air flue from the chimney, which isunder pressure as well. rlllnis heated air and products of combustionare circulated in chamber' 5 around the retort 8 and then powdered fueldischarge pass through flue 6 to the chimney. A portion of it isby-passed through the auxiliary iiue 7. The direct iue 6 is controlledby the damper 61 and the flue 7 is controlled by the damper 71, and thusby regulating the dampers 61 and 71 the extent of the heating of thepreheater 9 is controlled.

10 is the hopper for the coal which is to be distilled. This hopperdelivers into the U- shaped trough 9 of the preheater which, as stated,is provided with a feed screw 91 which is driven by the pulley or gear92 and carries the coal through the preheater trough, dropping itthrough the telescopic pipe 11 into the multiple screw feeder 12, whichis composed of a large outer tubular shell 121 in the bottom of which isa propeller feed screw 122. A pair of small semi-circular troughs ofdifferent lengths are disposed above the feed screw 122, the shorter one123 containing the feed screw 124 and the longer one 125 containing thefeed screw 126. These details are seen in Figs. 3 and 7. These feedscrews are actuated by a suitable gear train 127 of any convenientdesign, and they may be actuated separately or geared together in anysuitable and well-known way. This feed is made integral with the gasdelivery 17 and in central spaced relation therefrom. The multiplescrews and feed troughs of di'erent lengths deliver the coal evenly anddistribute it in the retort so that the heat is readily maintained andthe material is quickly and evenly heated.

The retort 8 isl made of steel boiler plate preferably, and cylindricalin form. 1t is supported on pairs of adjustable supporting rollers bywhich the relative elevation of the 'ends-and the inclination may becontrolled by suitable adjusting screw' 142 of usual construction. rllheopposite ends of the retort are provided with projecting tires 141 whichrest on the rollers for controlling and permitting the rotation of thesame. An annular gear 15 is provided at the discharge end of the retort,adapted to be driven by any suitable power means, not necessary to beshown. These parts are all standard commercial devices.

A residue discharge 13 for the retort is tubular in forni and contains ascrew conveyor 131 driven by a suitable gear or pulley 132 and deliversinto the vertical telescopic discharge pipe 134 which is controlled by astar valve 135 which maintains a gas tight connectionat that point. Thedischarge 13 is provided with a suitable stung box connection to thehead 81 of the retort 8. A pipe 16 is provided to deliver steam or fixedgas into the retort at the driven and discharge end.

rlhe gas o-take 17, as before indicated, is tubular in form andconnected by stung box 171 to the head 82 of the reto-rt 8. This gasdischarge connects to the telescopic gas odtake 18 `which delivers tocondensers 181 and scrubbers 182. The suction pump 183 draws neeen'eioff the product, as indicated, and discharges the non-condensible gasinto the holder or gas tank 184, where it is available for use. A partis delivered through pipe 185 to the furnace for fuel, as beforeindicated.

The smoke and products of combustion pass up the smoke iue 21. The downair flues 22 are disposed each side thereof and are separated b ycomparatively thin walls of fire brick 23. The heated air is delivereddownwardly by the blow fan 221 through header 222 and air connections223 to the combustion burners and entrained by the burners and passes onto the combustion chamber for heating the retort (see Figs. 2 and 11).

The retort 8 is divided by partitions 83, 83 and 84, into distillingchambers 85, 86 and 87 and discharge chamber 88. The partitions 83 arescalloped around the edges at 831 and contain a series of radial slots832 of appropriate size to retain the milling and tumblingl elements ineach chamber and provide a passage to the next succeeding chamber topermit the coal which is being distilled to pass freely on. Fineparticles pass ordinarily throng i the scallops 831.

` The partition 84 is not perforated and 1s scalloped at 841 and permitsthe discharge of the thoroughly pulverized residue from the coal intothe discharge chamber 88.

Within the discharge chamber 88 and connected to the Walls thereof are aseries of buckets 881 which are disposed radially and are adapted toconvey the residue from the coal upwardly and discharge it into thefixed hopper 136 which delivers into the discharge conduit 13, where thefeed screw 131 discharges the same, as indicated ln the first or maindistilling chamber 85 we supply milling elements of heat conductingmaterial, preferably chilled cast iron, which are angular in form, asindicated in Fig. 8, some having square ends, some trianl gular, andsome disks. It is only necessary that these elements have one flat sideand a scraping edge. In the first chamber some of these irregularelements are three inches and some six inches in diameter or crosssection in their shortest diameter. With these we provide 'a quantity ofballs or round elements (see Fig. 9), the exact spherical form not beingessential, from three to six inches in diameter, to assist in the flowor tumbling of the angular scraping milling elements so that they willscrape the sides of the retort and free it of any accumulation d-ue tothe fluxing of the coal that is being distilled. Also, the angularscraping elements serve to clean the balls and the balls react so thatthe milling elements are all kept clean, while at the same time scrapingand cleaning the retort. vThe coal is thus also broken up as soon as itis fiuxed in the process of distillin and the reduced pieces passed tothe secon compartment 86. The sticky condition of the .distilling massis overcome in the first pieces are further considerably reduced in sizeand similar milling and scraping elements are made use of, from one andone-half toet-wo inches in diameter, with preferably a somewhatincreased proportion of balls. These further pulverize the material,break up the surfaces and expose the same to the heating elements andthe heated walls of the retort. The material is still further reducedand passed in the smaller size to the third Alistilling chamber 87vwhere the tumbling and scraping elements are one and one-half inches indiameter and the final milling of the material is accomplished, where itis reduced to a powder and the residue delivered out to the dischargechamber 88 and carried away, as indicated.

The pipe 16 delivers steam or fiXed gas axially through the stuffing box161 through the hollow shaft of the screw feed 131 into the thirddistilling chamber 87, steam being preferred. The volume of steamdelivered at this point quickly carries -along with it all of thedistilled products and `carries them oft' through the gas discharge .17to the gas oif-take pipe 18, as before indicated. Because 0f the passageof this steam the distillate is not unduly heated and is passed offbefore it is injured, and the cracking of any of the products ofdistillation is thus reduced.

The powdered coal is delivered to the furnace 19. 191 is the feeder forthe hot powdered coal. 192 is `the conveyor screw controlled by thevariable gear 193. 194 is the coal. delivery nozzle. 195 is theconduit-for the primary air of combustion. 196 is the blower fan for theprimary air. 197 are the draft openings for secondary air.

Having described the complete apparatus, we will indicate itscourse ofoperation. The coal .in the hopper 10 drops into the Ypreheater 9 whereit is carried forward by the feed screw 91, thence through-the feed pipe11 to the multiple feed screw 12 where it is delivered into the firstcompartment 85 of the retort 8. The retort is heated on all Sides by theproducts of combustion circulating around the same, as indicated, andthe heating of the preheater is controlled by adjustment of the dampers61 and 71, as pointed out.

yCoal is distributed in the retort chamber 85 by the three feed screws122, 123 and 1,25, as indicated. In this retort are the tumbling,milling and scraping bodies, about half of which are round and fromthree to six inches in diameter, and the remainder are ofangular scraperform. as illustrated in Fig. 8. As the retort is slowly revolved and isadjusted to the proper inclination for the particular grade or kind ofcoal, the coal advancesin the same and is heated by these milling bodiesand the heated walls of the retort. The coalquickly fluxes and thistends to adhere to the walls of the retort or to the heating bodies, butthis is prevented by the angular elements because the motion imparted.to these bodies by the rotation lof the retort is less than the speed ofeither the periphery of the retort or the round milling bodies. Hencethey act as scraping devices and keep the walls of the retort and thesurfaces of the round milling elements and themselves free from any hardcarbonaceous dcposit which would insulate or out down the free heattransfer of these elements coacting with each other and the surface ofthe retort. Further, by reason of these angular elements an irregularsnake-like movement is imparted to the whole mass within the retort,thereby assisting in scraping the inner walls of the retort andadvancing the charge through the chamber. The entire mass is broken andthen dried out and becomes more or less like coke in character, andpasses readily through the first partition 83 tothe second distillingchamber 86. There the milling elements are of the same character but ofysmaller size. They act upon the coal to reduce it to smaller dimensionsand it is still further distilled and thence passes to the third anddistilling chamber 87, where the milling elements are comparativelysmall and of the same character, the proportion of the balls beingincreased.

The powdered coke or fuel is delivered direct from the improvedapparatus to the furnace 19, heated substantially to incandescence. Itpasses down through the conduitv 134 and the star valve 135. By thismethod the fuel after being powdered is not allowed to take up moistureand is delivered to the lire box in a. dry stato, thus conserving its`sensible heat. Beyond this, the fuel being hot readily ignites andburns, developing and delivering all the heat with great. economy in thefurnace. The fuel is delivered at the desired rate .through the downpipe 194 to the ignition chamber of the furnace. The fuel is supplied atthis point with primary air by the blower 196 delivering-through pipe195. Secondary air is admitted throughair ports 197 to the extentrequired to completely consume the fuel.- The heat of the furnace isregulated by the amount of fuel delivered.

The vapors that are developed by the heat would soon be cracked andinjured if allowed to remain in thehot retort. They arc carried away bya current of steam coming through the pipe 16 in a small volume which issuperheated and expanded.y The steam circulates freely through theretort and takes up any of the vapors and passes them along through theoutlet 17 to the gas off-take 18. There they pass to the condensers 181and serubbers 182.

These products are drawn along by the pump 183 and thus deliverel intothe gas holder. The pump is sufficient in capacity to maintain a minuspressure. The non-condensible gas is forced into tank 184 and preservedand storedl This non-condensible gas is readily available for use in thefurnace, which uses a part of the same to maint-ain the requiredtemperature in the retort. There is still an amount of gas that isavailable for general use for various purposes, as in internalcombustion engines or gas furnaces. All of the volatile products havebeen recovered. by this method, in their most valuable form.

The heat is very much conserved by our im proved apparatus. As soon asit has done its work of distillation, it is passed to the uptake fluewhere it heats the air in the down air fines which deliver this heatedair to the burners and furnace to help maintain combustion. The heatcontained in the air is thereby conserved. A considerable amount of thevolatiles would be recovered readily in a single retort, like thecompartment 85, but by providing the same in steps and ren ducing thesize of the milling elements, it is found that substantially all o f thevolatile content will be recoverable, and by making use of the usualcondensers and scrubbers the same is made available, either as liquid orgaseous products of the various forms derivable.

By dividing the retort into separate compartments the mass of millingand scraping elements can be disposed throughout the length of theretort as necessary for greatest eiciency. For example, the plasticstate of the coal during distillation occurs in the first chamber,therefore a greater heat transfer and milling and scraping action arenecessary, and so in this chamber we introduce a greater weight oflarger milling and scrap# in elements. By subjecting the mass undergoing distillation to successive steps in reduction and grading, Weinsure a thorough reduction and removal of all the volatiles.

It will thus appear that we utilize slack which is usually aninexpensive fuel and secure the valuable content in a simple andeffective manner. The plant may be operated by delivering the hotpowdered fuel to a ,briquetting machine. The distilling .and millingpart of the apparatus here shown is illustrated in application forpatent filed conl currently herewith Serial No. 62,855, for animprovement in process of distilling shale,

shale being a materialrequiring special treatment and special flushing.We desire to claim the process broadly in the present application andalso the apparatus, as defined in the appended claims.

Having thus described our invention what we claim as new and desire tosecure by Letters Patent is:

l. The continuous process of distilling solid carbonaceous material andburning the powdered residue as a fuel in an externally heated sealedtumbling barrel ball mill retort containing angular grinding elementsand ball grinding elements of heat conducting material consisting in,subjecting t-he carbonaceous material in lumpy condition to the actionof such retort and grinding elements to successively heat the saidcarbonaceous lumps until coking begins at the surface, grinding awaythecoked part and repeating the operation until the volatiles aredistilled away and the solid is reduced to a powder, delivering theheated powder toa combustion furnace, delivering primary air theretosufficient for ignition and partial combustion, and delivering asecondary air supply to producev complete combustion.

2. The continuous process of distilling solid carbonaceous material, andburning the powdered residue as a fuel in an externally heated sealedtumbling barrel ball mill retort containing angular grinding elementsand ball grinding elements of heat conducting material consisting in,subjecting the carbonaceous material in lumpy condition to the action ofsuch retort and grinding elements to successively heat the saidcarbonaceous lumps until coking begins at the surface, grinding away thecoked part and repeating the operation until the volatiles are.distilled away and the solid is reduced to a powder, and delivering theheated powder to a combustion furnace. v

3. The continuous process of 'dist-illing solid carbonaceous material inan externally heated sealed tumbling barrel ball mill retort containingangular grinding elementsl and ball grinding elements of heat conductingmaterial admixed 'in proportion to insure the flowing tumbling action ofsuch grinding elements consisting in, continuously introducing andsubjecting said material in a lumpy condition to the simultaneoustumbling action resulting from the rotation of said retort and thegrinding action of such elements to progressively heat the said materiallumps unt-il coking begins at the surface, grinding away the coked partand repeating the operation on the residuary lumps until thevolatilesare distilled away and the residue is reduced to a powder anddischarged. y

4. In a distilling apparatus for solid carbonaceou's material thecombination of an externally heated sealed tumbling barrel ball millretort, subdivided by foraminous partitions into a series of ball millchambers, each succeeding partit-ion having progressively smalleropenings, and each succeeding chamber containing'angular grinding ele-`ments and ball grinding elements of heat conducting material`admixed inproportion to insure the tiowing and tumbling action of.

such grinding elements of progressively smaller .size and ot' adimension to be rctained by each said foraminous partition, a feed i'orthe intalie end ot the retort comprising u series of troughs with screwconveyors delivering at diti'crent positions within the iirst chamber ofthe retort, 'a'. gas take-ott' opening above the level oi the solidcontents` a take-oli i'or the solid residue comprisingl a stationarycylindrical discharge connected to the retort by a trunnion withstufiing box, a Conveyor therein, a star valve in the discharge t'ormaintaining the retort gas sealed while delivering the solid residue, 'acombus-L tion furnace tor receiving and burning the said heated ponderedsolid residue, aprimar),1 air supply delivered into the stream ot iiuelypondered fuel to ignite the same and a se .'oi1dai' v air supply l'orcompleting the combustion.

ln a distilling apparatus for solid carbonaceous material thecombination ot an externally heated sealed tumbling barrel ball millretort, subdivided by foramiuous partitions into a series ot ball millchambers, each succeeding partition having progressively smalleropenings, and each succeeding chamber containing angular grindingelements and ball grinding elements ot' heat conducting material admixedin proportion to insure the flowing and tumbling' action otl suchgrinding elements of progressively smaller size and ot la dimension tobe retained by each said foraminous partition, a feed t'or the intakeend ot the retort comprising a se'- ries otl troughs with screwconveyors delivering at ditterent positions within the first chamber oflthe retort, a gas take-ott opening above the level'of the solidcontents, a takeofl' tor the solid residue comprising a stationarycylindrical dischargeI connected to the retort by a trunnion withstufling box, a conveyor therein, a star valve in the dis charge tormaintaining the retort gas sealed while delivering the solid residue,and a combustion furnace for receiving and burning the said heatedpowdered Solid residue.

6. In a distilling apparatus for solid carbonaceous material thecombination yof an externally heated sealed tumbling barrel ball millretortsubdivided by oraminous partitions into a series of ball millchambers, each succeeding partition having progressively smalleropenings, and each succeeding chamber containing angular grindingelements and ball grinding elements ot heatl conducting material admixedin proportion to insure the tlowing and tumbling action of such grindingelements of progressively smaller size and ot a dimension .to beretained by each said foraminous partition, a teed for the in-V take endof the retort comprising a series of troughs with screw conveyorsdellvering at different positions Within the tirst chamber of theretort, a gas take-oft' opening above the level of the solid contents, atake-olf :tor the solid residue comprising a stationary cylindricaldischarge connected to the retort by a trunnion with stuffing box, aconveyor therein, and a star valve in the discharge for maintaining theretort gas sealed while deliverinfr the solid residue.

In a distilling apparatus forlsolid car bonaceous material thecombination ot' an externally heated sealed tumbling barrel ball millretort., angular grinding elements and ball grinding elements Within thesaid retort admixed in proportion to insure the flowing and tumblingaction of such grinding elements, means for delivering said solidcarbonaceous material to the retort, a gas take-ofi' opening above thelevel ol the `solid contents, a takeott for the solid powdered residuecomprising a stationary cylindrical discharge connected to the retort bya trunnion, al conveyor therein, a star valve in the discharge formaintaining the retort gas sealed while delivering the solid residue,and a combustion furnace for receiving and burning the heated powderedsolid residue as specified.

8. In a distilling apparatus for solid carbonaceous material thecombination of an externally heated sealed tumbling barrel ball millretort, angular grinding elements and ball grinding elements within thesaid retort, admixed in proportion to insure the iiowing and tumblingaction of such grinding elements, means for delivering solidcarbonaceous material to the retort, a gas takeott' open/ing above thelevel of the solid contents, a take-oit tor the solid powdered residuecomprising a stationary cylindrical discharge connected to the retort bya t-runnion, a conveyor therein, and means to maintain the outlet sealedagainst gas.

9. In an apparatus for heat treating solid material the combination ofan externally heated tumbling barrel ball mill retort, subdivided byforaminous partitions into a series of ball mill chambers, eachsucceeding partition having progressively smaller openings and eachsucceeding chamber containing angular grinding elements and ballgrinding elements of heat conducting material admiXed in proportion toinsure the flowing and tumbling action of such grinding elements ofprogressively smaller Size and'ot a dimension to be retained by eachsaid foraminous partition, a feed for the intake end of the retort and atake-oit discharge for the pulverized material from theretortns'ispecitied.

l0. In an apparatus for heat treating' solid material the combination ofan externally heated tumbling barrel ball mill retort containing angulargrinding elements and ball grinding elements ot heat conductinginatorial admixed in proportion to insure the Howing and tumbling actionof such grinding elements, a 'feed for the intake end of the retort anda take-G` discharge for the pnlverized material from the retort asspecified.

11. An apparatus for heat treating solid material the combination of anexternally heated tumbling barrel hall mill retort and angular grindingelements and ball grinding i0 elements of heat conducting materialadrnixed in proportion to insure the flowing and tumbling action of Suchgrinding elements disposed therein to insure the grindin and tumblingaction of solid material ing ground in the mill.

In Witness whereof We have hereunto set our hands. l

HARRY S. REED. RALPH D.` LAMIE.

